Administration of the MapR Database is done primarily via the command line (maprcli) or with the MapR Control System (MCS). Regardless of whether the MapR Database table is used for binary files or JSON documents, the same types of commands are used with slightly different parameter
options. MapR Database administration is associated with tables, columns and column families, and table regions.

The MapR Data Access Gateway is a service that acts as a proxy and gateway for translating requests between lightweight
client applications and the MapR cluster. This section describes considerations when upgrading the service, how to modify
configuration settings, and how to administer and manage the service.

YARN Resource Calculation Based on Labels

This new approach to YARN resource allocation enables the cluster LBS configuration to
compute the resources that are allowed for each queue. It also uses LBS to assign
containers to the correct queues to preempt containers, and to prevent resource overuse.
The LBS approach to YARN resource allocation relies on:

Resource computation (memory, CPU, disks) based on labels for each queue.

Per-label preemption threshold.

Example of LBS Resource Computation

For example, imagine that you have the following resources:

Using the former fair-share resource distribution results in the following:

Using the new LBS resource distribution results in the following:

Understanding LBS preemption thresholds

Before LBS, preemption occurred by default when an entire cluster became 80% full
(yarn.scheduler.fair.preemption.cluster-utilization-threshold=0.8f).
With LBS, preemption occurs per labeled resource, as that resource becomes 80% full.

Descriptions of New Properties When Using LBS

defaultQueueLabel

Assigned to all new queues and existing queues that do not have a label (excluding
the root queue).

For example,
root.%username% queue is created if you submit a new job
without queue information and property
yarn.scheduler.fair.user-as-default-queue is true.

Allows
enabling or disabling (default) preemption of the threshold per-label. To overcome
the default and start container preemption when the threshold of the label is
exceeded, change this property to true.